1. Field of the Invention
This invention relates to an ink cartridge of a jet printer, and particularly to a device for preventing from ink interruption in a printing head of an ink cartridge in a printer
2. Description of the Prior Art
In the conventional jet printer, the ink is loaded in a cartridge, and the ink jetted on the printing paper is controlled with a sparager; when ink in the cartridge is used up, the cartridge has to be replaced for further printing operation; however, the ink cartridge supplied by the original manufacturer is considerably expensive, i.e., a user to print a lot of papers will spend a lot of money.
In the conventional ink cartridge of a jet printer, the ink chamber of the ink cartridge is usually loaded with an equalization air bladder or a piece of sponge for soaking and supplying inks. The ink cartridge supplied by the original manufacturer usually has an equal pressure in the ink chamber during the automatic manufacturing process, and there will be no leak during printing operation.
When refilling ink into a conventional hollow ink cartridge, and if such ink cartridge is furnished with an equalization air-bladder in the ink chamber thereof, a sticky tape should be used to close the air vent of the maze passage on the bottom of the ink cartridge so as to prevent ink from leaking; then, the intake hole of the air-bladder should also be closed with sticky tape so as to maintain equalization of pressure; then, use a sharp point to press the seal bead out of its position so as to provide a refilling hole. Take a suitable amount of ink with a syringe, and then inject the ink into the refilling hole on the ink cartridge slowly until the cartridge being full; use a plastic plug to seal the refilling hole, and then tear off the sticky tapes on the intake hole and on the bottom of the ink cartridge respectively; it is quite often that the opening end of the maze passage or the jet nozzle will have a leakage of ink after the sticky tape on the bottom of cartridge being removed because of the pressure in the ink chamber not being equalized. To overcome such leakage, the only method is to rub off the ink leaked slowly until the leak stopped.
The air bladder of the ink cartridge is usually furnished in the prime chamber; a second chamber is furnished between the prime chamber and the printing head. Between the two chambers, there is a fine mesh used for balancing the pressure difference thereof so as to have the ink flowed evenly into the storage chamber of the sprayer in the printing head, and also to prevent impurities in the ink of prime chamber from entering the second chamber.
When the ink cartridge on a printer fails to print continuously, the major cause is that the sprayer in the printing head is in short supply of ink, i.e., lack of sufficient ink flowing through the passage defined by the bearing member; in other words, if too much air enters the second chamber in the printing head, such air would enter the storage chamber of the sprayer to cause interruption of ink, i.e., having no ink to spray out; in the event of no ink to spray out of the sprayer for a considerable time, the sprayer might be burned out.